An operator engaged in an electronic engineering career or an inflammable and explosives-related career will often contact the devices, byproducts or materials which are very sensitive to electrostatic or body voltage. Therefore, it should be careful to keep grounding between the operator and an operating environment whatever the ground connection between the operator and the operating environment is perform through an electrostatic ground connection or an alternating current ground connection.
Generally, a good workbench will be required for considering how to keep the ground connection well between the operator and a surface of the workbench. The main purpose of the abovementioned requirement is for approaching an isoelectric effect between every material, which is sensitive to the electrostatic voltage whatever it focuses on the electrostatic ground connection or a combination of the electrostatic ground connection and a power ground connection, in order to prevent the damage and hurt of the products and environments by an electrostatic discharge. The ground connection of the traditional workbench is performed by measuring the ground resistance of the workbench surface and that of the operator, and then monitors these two objects. For the stricter requirement, it also monitors the resistance of the equipment (electronic microscope, for instance) on the workbench.
The prior art is performed by pre-setting a fixed analog limit-value (ex: a voltage) of the ground resistance of the operator, the workbench and the equipment separately. And then, the real measured analog values of the traditional workbench will be compared with these analog limit-values in order to determine whether the real measured values are still in a normal range. The prior art has two disadvantages as follows:                (1) The prior art compares the value from the monitor and the value from the pre-set value without determining the real value. Not determining the real value can cause some mistakes or problems of reliabilities due to the lack of precision in the calculations of measured value.        (2) According to the prior art, the parameter settings of systems will not vary depending on the different environment, which will cause inconvenience and the limit of the application.        